B K Mueller 521-406HN Black Pipe Cap 1.25 in 5 Pack

Product Description

The B K Mueller Industries 521-406HN is a black pipe cap sized for 1.25-inch nominal pipe. Pipe caps are threaded end closures used to seal the open end of a pipe, preventing flow, contamination, or pressure loss in a piping system. This cap is finished in black, indicating a black steel or black iron construction typical for gas distribution, fire sprinkler rough-in, and general industrial piping applications. Installation is performed by licensed plumbers, pipefitters, or gas technicians working on threaded black iron pipe systems.

This cap is suited for residential and commercial applications where black iron or black steel threaded pipe is used. Common scenarios include capping unused branch outlets on gas distribution manifolds, temporarily or permanently closing runs during rough-in, and sealing test ports. The package contains 5 caps per unit, making it practical for service vehicles and job-site stockpiling on larger installations.

Key Features

• 1.25-inch nominal size for direct threaded fit on standard black iron pipe
• Black finish consistent with black iron gas and industrial pipe systems
• Packaged in quantities of 5 for efficient job-site supply
• Threaded end-closure design seals pipe openings securely

Compatibility

Designed as an OEM-style replacement and standard fitment for 1.25-inch nominal threaded black iron pipe systems used in gas, industrial, and mechanical piping applications.

Installation Notes

Black pipe caps are installed by licensed plumbers, gas fitters, or pipefitters working on threaded iron pipe systems. Always shut off gas or fluid supply and relieve system pressure before removing or installing any pipe fitting. Apply thread sealant or pipe tape appropriate for the service medium before threading the cap onto the pipe end. Work must comply with local plumbing and fuel gas codes, including IFGC requirements where applicable.